The present invention relates to a suction pile designed to be sunk into a seabed, in particular into a seabed of shallow depth.
Suction piles make it possible to anchor installations or structures in the seabed in order to hold them in a fixed position. These well known suction piles comprise a cylindrical wall and, inside, a partition which divides the cylindrical wall into two chambers that are sealed relative to one another. The cylindrical wall then has an open suction end suitable for being pressed against the seabed so as to close off one of said chambers. This chamber is then filled with water and pumping means are suitable for extracting the water from said chamber in order to create a negative pressure therein and cause the cylindrical wall to sink into the seabed. Therefore, gradually as the pumping takes place, the cylindrical wall sinks into the seabed and the suction pile is then anchored therein.
Reference may notably be made to document U.S. Pat. No. 6,488,446 which describes suction piles of the aforementioned type, in which said partition which divides the cylindrical wall into two chambers can be moved for the purpose of increasing the volume of the other chamber which is totally sealed and which makes it possible to increase the buoyancy notably of the suction pile. These technical features are designed to make said suction piles easier to transport.
Furthermore, the sinking of the cylindrical wall into the seabed is easier if the depth of said seabed is great. Specifically, the hydrostatic pressure which increases with the depth helps to apply forces to the suction pile, which forces promote its sinking.
However, at shallow depths, for example less than 50 meters, the forces that are applied to the top end of the suction pile which, for example, has a length of 15 meters, are relatively weak since they are related to the hydrostatic pressure that then prevails at a depth of 35 meters.
Therefore, a problem that arises and that the present invention aims to solve is making it easier for the suction piles to penetrate seabeds of shallow depth.